When to change pre amp tubes

[base341]

There's alot of talk about power tube selection and when to change them but not much on preamp tubes.
I have a Herbert that I think is an '06.
I think it has the original ruby's in it.
How often and what should I be looking to put in the preamp section?

 

[RJF]

When my Dual rectifier was broke down and I was at the Mesa factory, one of the mesa guys told me that it's best to just not mess with preamp tubes unless one actually goes bad. He said a lot of times people will bend the pins, or worse bend one of the pin sockets in the amp and you then have bigger problems.

But.... What I would do is make sure you have a Ruby 12ax7ac5 HG+ in your V1 and I believe in V5? to minimize noise. My Herbert is a late '08 and I believe it had either all TAD or TAD and a couple Rubys. Been 6 months or so since I looked and can't recall precisely. I would change out your V1 if you haven't done so with an HG+ and if it sounds good and is quiet then I say you've got a good preamp section.

 

[PaulyPanacea]

i change my pres when the amp starts to sound different or noise is present. Just kinda play it by ear so to speak

 

[Ventura]

i change my pres when the amp starts to sound different or noise is present. Just kinda play it by ear so to speak

Lots of hiss, periodic crackling, pops and so forth... I change them. But man, they can last years before you need to mess with 'em. Noise, as Pauly said, can include microphonics, weird feedbacks, and more.

V.

 

[PaulyPanacea]

...YEAH....what V said!

 

[base341]

I sometimes use a bb preamp for a clean boost on channel 2- and noticed last night when it's on I'm getting a loud hiss.. It started me thinking maybe one of the preamp tubes is toast..
Maybe I should just replace all while I'm at it.

 

[Ventura]

I sometimes use a bb preamp for a clean boost on channel 2- and noticed last night when it's on I'm getting a loud hiss.. It started me thinking maybe one of the preamp tubes is toast..
Maybe I should just replace all while I'm at it.

No, maybe you should try not using your BB preamp and turn up the amp instead - if it's better without it, then it's not a preamp issue. Secondly, hi gain settings on the amp come with inherent hiss. If ya really just gotsta get in there and muck with your preamp tubes, I guess do it. But seriously, I don't think you need to do it unless you get NOTICEABLE noise.

Peace,
V.

 

[base341]

I sometimes use a bb preamp for a clean boost on channel 2- and noticed last night when it's on I'm getting a loud hiss.. It started me thinking maybe one of the preamp tubes is toast..
Maybe I should just replace all while I'm at it.

No, maybe you should try not using your BB preamp and turn up the amp instead - if it's better without it, then it's not a preamp issue. Secondly, hi gain settings on the amp come with inherent hiss. If ya really just gotsta get in there and muck with your preamp tubes, I guess do it. But seriously, I don't think you need to do it unless you get NOTICEABLE noise.

Peace,
V.

I played for a couple hours today and it's back to normal. It must have just been a fluke thing.
I guess there's no need to replace pre tubes unless one blows.

 

[Ventura]

I sometimes use a bb preamp for a clean boost on channel 2- and noticed last night when it's on I'm getting a loud hiss.. It started me thinking maybe one of the preamp tubes is toast..
Maybe I should just replace all while I'm at it.

No, maybe you should try not using your BB preamp and turn up the amp instead - if it's better without it, then it's not a preamp issue. Secondly, hi gain settings on the amp come with inherent hiss. If ya really just gotsta get in there and muck with your preamp tubes, I guess do it. But seriously, I don't think you need to do it unless you get NOTICEABLE noise.

Peace,
V.

I played for a couple hours today and it's back to normal. It must have just been a fluke thing.
I guess there's no need to replace pre tubes unless one blows.

Or you get the above mentioned sonic anomolies.

Peace,
V.